1、Long Life Span: Made of excellent plate, our relay module is durable and wear resistance, providing the product with a long life span. 2、Brightness Detection: The board can adjust the photosensitive sensitivity through the potentiometer, and has its own relay, which can be used as a variety of brightness detection control switches. 3、High Accuracy: The relay module is sensitive to light. It can adjust the state in time according to the light chnage. 4、External Switch: Through an external switch, you can conveniently and efficiently manipulate the condition of the relay module. 5、Wide Application: Our OPTO isolation relay module can be used in street lights, which are automatically turned on at night and automatically turned off during the day, as well as other equipment that requires automation. Item Type: Photosensitive Relay Module Output Type: Output Switch Control Capacity: Maximum 10A Detection Frequency: 1MHz 4 x Relay Module 4 x Photoresistance